In challenging the virtues of decentralization, Shelby was challenging an idea that in the past fifteen years has seized the imagination of businessmen, academics, scientists, and technologists everywhere. In business, management theories like reengineering advocated replacing supervisors and managers with self-managed teams that were responsible for solving most problems on their own, while more utopian thinkers deemed the corporation itself outmoded. In physics and biology scientists paid increasing attention to self-organizing, decentralized systems—like ant colonies or beehives—which, even without a center, proved robust and adaptable. And social scientists placed renewed emphasis on the importance of social networks, which allow people to connect and coordinate with each other without a single person being in charge. Most important, of course, was the rise of the Internet—in some respects, the most visible decentralized system in the world—and of corollary technologies like peer-to-peer file sharing (exemplified by Napster), which offered a clear demonstration of the possibilities (economic, organizational, and more) that decentralization had to offer.

The idea of the wisdom of crowds also takes decentralization as a given and a good, since it implies that if you set a crowd of self- interested, independent people to work in a decentralized way on the same problem, instead of trying to direct their efforts from the top down, their collective solution is likely to be better than any other solution you could come up with. American intelligence agents and analysts were self-interested, independent people working in a decentralized way on roughly the same problem (keeping the country safe). So what went wrong? Why did those agents not produce a better forecast? Was decentralization really the problem?

BEFORE WE ANSWER THAT question, we need to answer a simpler one first: What do we mean by “decentralization,” anyway? It’s a capacious term, and in the past few years it’s been tossed around more freely than ever. Flocks of birds, free-market economies, cities, peer-to-peer computer networks: these are all considered examples of decentralization. Yet so, too, in other contexts, are the American public-school system and the modern corporation. These systems are dramatically different from each other, but they do have this in common: in each, power does not fully reside in one central location, and many of the important decisions are made by individuals based on their own local and specific knowledge rather than by an omniscient or farseeing planner.

In terms of decision making and problem solving, there are a couple of things about decentralization that really matter. It fosters, and in turn is fed by, specialization—of labor, interest, attention, or what have you. Specialization, as we’ve known since Adam Smith, tends to make people more productive and efficient. And it increases the scope and the diversity of the opinions and information in the system (even if each individual person’s interests become more narrow).

Decentralization is also crucial to what the economist Friedrich Hayek described as tacit knowledge. Tacit knowledge is knowledge that can’t be easily summarized or conveyed to others, because it is specific to a particular place or job or experience, but it is nonetheless tremendously valuable. (In fact, figuring out how to take advantage of individuals’ tacit knowledge is a central challenge for any.group or organization.) Connected with this is the assumption that is at the heart of decentralization, namely that the closer a person is to a problem, the more likely he or she is to have a good solution to it. This practice dates hack to ancient Athens, where decisions about local festivals were left up to the demes, as opposed to the Athenian assembly, and regional magistrates handled most nonserious crimes, It can also be seen in Exodus, where Moses’ father-in-law counseled him to judge only in ‘great matter[s]” and to leave all other decisions to local rulers.

Decentralization’s great strength is that it encourages independence and specialization on the one hand while still allowing people to coordinate their activities and solve difficult problems on the other. Decentralization’s great weakness is that there’s no guarantee that valuable information which is uncovered in one part of the system will find its way through the rest of the system. Sometimes valuable information never gets disseminated, making it less useful than it otherwise would be. What you’d like is a way for individuals to specialize and to acquire local knowledge—which increases the total amount of information available in the system— while also being able to aggregate that local knowledge and private information into a collective whole, much as Google relies on the local knowledge of millions of Web-page operators to make Google searches ever-smarter and ever-quicker. To accomplish this, any “crowd”—whether it be a market, a corporation, or an intelligence agency—needs to find the right balance between the two imperatives: making individual knowledge globally and collectively useful (as we know it can be), while still allowing it to remain resolutely specific and local.